Study suggests the impact of global warming will be quicker and more catastrophic than envisioned, writes Chris Mooney.

Climate scientists’ global warning

By Chris Mooney

Study suggests the impact of global warming will be quicker and more catastrophic than envisioned, writes Chris Mooney.

If the scientists’ study is right, sights like that in Lake Argentina, where chunks of ice broke off the Perito Moreno Glacier this month, could become more common. Photo / AP

An influential group of scientists led by James Hansen, the former Nasa scientist often credited with having drawn the first major attention to climate change in 1988 congressional testimony, has published a dire climate study that suggests the impact of global warming will be quicker and more catastrophic than generally envisioned.

The research invokes collapsing ice sheets, violent megastorms and even the hurling of boulders by giant waves in its quest to suggest that even 2C of global warming above pre-industrial levels would be far too much. Hansen has called it the most important work he has ever done.

The sweeping paper, 52 pages in length and with 19 authors, draws on evidence from ancient climate change or “paleo-climatology”, as well as climate experiments using computer models and some modern observations. Calling it a “paper” really isn’t quite right – it’s actually a synthesis of a wide range of old and new evidence.

“I think almost everybody who’s really familiar with both paleo and modern is now very concerned that we are approaching, if we have not passed, the points at which we have locked in really big changes for young people and future generations,” Hansen said.

The research, appearing on Wednesday in the open-access journal Atmospheric Chemistry and Physics, has had a long and controversial path to life, having first appeared as a “discussion paper” in the same journal, subject to live, online peer review – a novel but increasingly influential form of scientific publishing. Hansen first told the press about the research last year, before this process was completed, leading to criticism from some journalists and also fellow scientists that he might be jumping the gun.

What ensued was a high-profile debate, both because of the dramatic claims and Hansen’s formidable reputation. And his numerous co-authors, including Greenland and Antarctic ice experts and a leader of the United Nations’ Intergovernmental Panel on Climate Change, were nothing to be sniffed at.

After record downloads for the study and an intense public review process, a revised version of the paper has now been accepted, according to both Hansen and Barbara Ferreira, media and communications manager for the European Geophysical Union, which publishes Atmospheric Chemistry and Physics. Indeed, the article is now freely readable on the Atmospheric Chemistry and Physics website.